It has previously been suggested to directly mine metal values from sulfide ores. While theoretically the idea is quite feasible from an engineering standpoint, previous attempts to accomplish such electrochemical mining met with limited success. Initially, the reaction would proceed as theorized, but after only a relatively short application of electrical current to the ore body, the electrodes would polarize due to the buildup of an insulating shield of sulfur on the surface of the ore. Current efficiencies would rapidly deteriorate and the electrolysis would slow to an unacceptable rate. Continued application of electrical energy would soon result in total polarization of the electrodes and termination of economic electrolysis.
Applicant's co-pending application Ser. No. 470,807 sets forth a method whereby these difficulties and shortcomings have been overcome to thereby efficiently and continuously electrochemically mine metal values from sulfide ore deposits. Having solved the problem of continuous electrolysis, it has become apparent that it is more desirable to recover the valuable metals from such sulfide ore deposits in a condition which minimizes subsequent refining and purifying of the metal values. Additionally, because most valuable sulfide ore deposits would be preferably worked for their copper values, it is desirable to obtain the copper from said deposits as metallic copper in a state which can be either utilized as recovered or which requires a minimum of further refining and purification. Many of such sulfide ore deposits additionally contain another metal, the more frequent metal found in combination with copper being iron. Often times, such iron is present in a substantial proportion of the metal values. Under such circumstances, it is often desirable to additionally recover the iron in a purified form as possible to likewise reduce further purification and refining steps.
It is therefore an object of the present invention to provide a method for electrochemically mining copper sulfide ore bodies and the direct recovery from said ore bodies of metallic copper values.
It is an additional object of the present invention to provide a method for simultaneously reducing both copper and iron in sulfide ore bodies containing the same to produce finely divided copper and iron.
These and other objects of the present invention will become apparent to those skilled in the art from the description of the invention which follows.